1. Technical Field
The present invention relates to a MEMS vibrator, a method of manufacturing a MEMS vibrator, an electronic device, and a moving object.
2. Related Art
Generally, electro-mechanical system structures (for example, vibrators, filters, acceleration sensors, motors, and the like) are known which include a mechanically displaceable structure called a MEMS (Micro Electro Mechanical System) device formed using a semiconductor micromachining technique. Among the structures, a MEMS vibrator is easily manufactured by incorporating a drive circuit of a vibrator or a circuit that amplifies a change of vibration, as compared with a vibrator and a resonator using a quartz crystal or a dielectric, and is advantageous to miniaturization and high functionality. Therefore, its applications are widespread.
As a representative example of the MEMS vibrator in the related art, a beam vibrator vibrating in the thickness direction of a substrate is known. The beam vibrator is a vibrator which is constituted by a lower electrode (fixed electrode) provided on the substrate, an upper electrode (movable electrode) provided at a distance from the lower electrode, and the like. As the beam vibrator, a clamped-free beam, a clamped-clamped beam, a free-free beam and the like are known depending on a method of supporting the movable electrode.
JP-A-2012-85085 discloses a MEMS vibrator having a structure in which a fixed portion extends from an insulating portion provided on a substrate in a direction intersecting the insulating portion, and a movable electrode further extends from a fixed portion in a direction intersecting the fixed portion.
However, since vibration leaking from the movable electrode between the movable electrode and the fixed portion which are provided in an intersection manner and between the fixed portion and the insulating portion which are provided in an intersection manner is refracted and propagated, there may be a concern of a reduction in a Q value of the MEMS vibrator or a fluctuation in the characteristics of a vibration frequency or the like due to distortion occurring from the vibration leaking at each of the intersection points between the movable electrode and the fixed portion and between the fixed portion and the insulating portion.